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Indexed by:期刊论文

Date of Publication:2011-02-01

Journal:JOURNAL OF POROUS MATERIALS

Included Journals:SCIE、EI

Volume:18

Issue:1

Page Number:23-30

ISSN No.:1380-2224

Key Words:Nanocasting; Ordered mesoporous carbons; Pore structure; Electric double-layer capacitor; Electrode disc thickness

Abstract:Various nanocast ordered mesoporous carbons (OMCs) were synthesized using mesoporous silicas such as SBA-15, SBA-16, KIT-6, SBA-3 and MCM-48 as templates via nanocasting pathway. The structures of OMCs were analyzed by X-ray diffraction, transmission electron microscope and nitrogen sorption technique. These OMCs with well-defined pore structure were used as model electrode materials for investigating the influence of pore structure on their double layer capacitances. The cyclic voltammetry and galvanostatic charge/discharge measurements were conducted to estimate the capacitive behaviour of OMCs. The results show that the mesopore structures of OMCs play an important role in improving surface utilization for the formation of electrical double layer. OMCs synthesized from SBA-15 and SBA-16 show great advantage over others because their micropores are being easy accessible through the mesopores, thus allowing rapid electrolyte ion diffusion. To achieve a higher specific capacitance (mu F cm(-2)), the optimized amount ratio between micropore and mesopore needs to be controlled. In addition, great impact of the electrode disc thickness on the capacitive performance was demonstrated by a series of careful measurements.